In a gas turbine engine used for propulsion, a fan case and a smaller diameter compressor case cooperate to radially bound an annular fan duct. Structural guide vanes (SGVs) span across the fan duct to de-swirl working medium fluid such as air flowing there through. The outer and inner extremities of the vanes are connected to the fan and compressor cases respectively.
On occasion, an aircraft will have static build up as it travels through the air, since air does contain electrons. More importantly, aircraft are occasionally subjected to lightning strikes. In both instances, grounding of the fan case is highly desirable.
One of the functions of SGVs is to serve as an electrical path to ground. The SGVs are connected to the fan case and the compressor case. When both cases serve as electrical grounds, the SGVs ensure that the two grounds are in good electrical contact so that neither case has a higher electrical potential. At the same time, all the mating interfaces are coated with a non-conductive paint and/or primer in order to prevent electric current to contact any part of the gas turbine engine. Additional mounting or structural components have been required to be added in order to secure a separate ground strap to provide a path for electrical current to a ground from the fan case to the compressor case.